Due to the difference in charges, heparin has been documented to interact with over 100 proteins. 23 As the most negatively charged biological molecule known, heparin has a strong ability to interfere with the functioning of positively charged molecules. 44–46 Unfractionated heparin is a mixture of glycosaminoglycans of variable lengths and molecular weights ranging from 3 to 30 kD. Recent studies have shown the potential benefit of unfractionated heparin in antagonizing mechanisms responsible for DND associated with aSAH. 12, 19, 21, 38 Neuroimaging many years after aSAH frequently demonstrates findings of global cerebral atrophy, ventricular dilation, and sulcal enlargement, findings similar to those observed in other disease processes with cognitive dysfunction.

Inflammatory responses of the same sort result in similar patterns of cognitive dysfunction in diseases as varied as Alzheimer’s disease, HIV, infection, traumatic brain injury, and normal aging. Additionally, long-term cognitive dysfunction may also be significantly related to neuroinflammation. 15, 22, 35, 46, 48 The systemic inflammatory response has been demonstrated to correlate with cerebral vasospasm. Subarachnoid hemorrhage induces a significant inflammatory response involving numerous cytokines, chemokines, complement, leukocytes, and microglia. Cognitive dysfunction after aSAH is arguably one of the most critical manifestations of DND.

39 Collectively, these pathologic processes result in delayed neurological deficits (DND). 6, 25, 36, 37, 49, 52, 59 Specifically, microthrombi and intraparenchymal vasoconstriction have been associated with increased expression of membrane P-Selectin and decreased nitric oxide (NO), as well as ensuing adjacent neuronal apoptosis. 14, 24Īdditional brain injury occurring after the initial hemorrhage may be due to cerebral vasospasm, inflammation, nonobstructive hydrocephalus, microthombi, cortical spreading depolarization, and neuronal cell death. 26 Although aSAH-related cognitive dysfunction may improve over time, most patients report lifelong cognitive deficits. 1, 18 Verbal memory, visual memory, language, and executive function are the most commonly impaired cognitive domains. 1, 28 Cognitive impairments often co-manifest with life-changing psychosocial problems, with 59% of surviving patients unable to return to their previous occupation, and up to 93% demonstrating deficits in activities of daily living. Long-term cognitive impairment occurs in up to 70% of patients surviving the initial hemorrhage. 31 With improvements in aSAH treatment and ICU care, more patients who have experienced aSAH are surviving the initial event. A neurysmal subarachnoid hemorrhage (aSAH) is a rare, devastating cause of stroke that carries a case fatality rate of up to 67%.

Heparin drip